From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Chen, Tiejun" <tiejun.chen@intel.com>
Subject: Re: [v4][PATCH 14/19] tools/libxl: detect and avoid
 conflicts with RDM
Date: Fri, 26 Jun 2015 13:45:02 +0800
Message-ID: <558CE6DE.8010204@intel.com>
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	<1435053450-25131-15-git-send-email-tiejun.chen@intel.com>
	<20150625112352.GJ6545@zion.uk.xensource.com>
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To: Wei Liu <wei.liu2@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>, Ian Jackson <ian.jackson@eu.citrix.com>, Ian Campbell <ian.campbell@citrix.com>, xen-devel@lists.xen.org
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On 2015/6/25 19:23, Wei Liu wrote:
> On Tue, Jun 23, 2015 at 05:57:25PM +0800, Tiejun Chen wrote:
>> While building a VM, HVM domain builder provides struct hvm_info_table{}
>> to help hvmloader. Currently it includes two fields to construct guest
>> e820 table by hvmloader, low_mem_pgend and high_mem_pgend. So we should
>> check them to fix any conflict with RAM.
>>
>
> RAM -> RDM?

Fixed.

>
>> RMRR can reside in address space beyond 4G theoretically, but we never

[snip]

>> +static struct xen_reserved_device_memory
>> +*xc_device_get_rdm(libxl__gc *gc,
>> +                   uint32_t flag,
>> +                   uint16_t seg,
>> +                   uint8_t bus,
>> +                   uint8_t devfn,
>> +                   unsigned int *nr_entries)
>
> I just notice this function lives in libxl_dm.c. The function should be
> renamed to libxl__xc_device_get_rdm.
>
> This function should return proper libxl error code (ERROR_FAIL or
> something more appropriate). The allocated RDM entries should be

ERROR_FAIL is better.

So refactor this function after address your all comments,

static int
libxl__xc_device_get_rdm(libxl__gc *gc,
                          uint32_t flag,
                          uint16_t seg,
                          uint8_t bus,
                          uint8_t devfn,
                          unsigned int *nr_entries,
                          struct xen_reserved_device_memory *xrdm)
{
     int rc;

     /*
      * We really can't presume how many entries we can get in advance.
      */
     *nr_entries = 0;
     rc = xc_reserved_device_memory_map(CTX->xch, flag, seg, bus, devfn,
                                        NULL, nr_entries);
     assert(rc <= 0);
     /* "0" means we have no any rdm entry. */
     if (!rc)
 
 
        94,22          3%
     /* "0" means we have no any rdm entry. */
     if (!rc)
         goto out;

     if (errno == ENOBUFS) {
         xrdm = libxl__malloc(gc,
                              *nr_entries *
                              sizeof(xen_reserved_device_memory_t));
         rc = xc_reserved_device_memory_map(CTX->xch, flag, seg, bus, devfn,
                                            xrdm, nr_entries);
         if (rc) {
             LOG(ERROR, "Could not get reserved device memory maps.\n");
             rc = ERROR_FAIL;
         }
     } else {
         LOG(ERROR, "Could not get reserved device memory maps.\n");
         rc = ERROR_FAIL;
     }

  out:
     if (rc) {
         *nr_entries = 0;
         xrdm = NULL;
     }
     return rc;
}

Thanks
Tiejun